"If Donald Trump does become president, he's going to become a very powerful man and he's not going to forgive Sen. Cruz for what he did yesterday," says Nick Allman.

CLEVELAND, Ohio — One of the youngest Texas delegates attending the Republican National Convention, Nick Allman, made a wager with a buddy in the group whether Ted Cruz would endorse Donald Trump on Wednesday night.

The 23-year-old lost $100.

"I don't necessarily agree with what Ted did, but I have serious respect for him," Allman told The Hollywood Reporter on Thursday, the final day of the RNC. "That took major, major courage."

Cruz was booed off stage Wednesday night after he refused to endorse Trump for president. Cruz and Trump were locked in a bitter battle for months during the primary season as the two men vied for the GOP nomination.

Allman, a San Antonio resident, says Cruz may feel the repercussions of his decision should Trump beat Hillary Clinton in the fall.

"If Donald Trump does become president, he's going to become a very powerful man, and he's not going to forgive Sen. Cruz for what he did yesterday," Allman says. "I was walking out and some of my fellow Texans were saying 'he's done,' they're never voting for him again.'

Yet, Allman says he is still a fan of Cruz. "This wouldn't turn me off," he adds, calling the move "gutsy."

Still, Almman says Cruz might be in trouble.

"There is no way, as far as politics are concerned that, that was a smart move for his career," Allman says. "I mean, I get it. Trump insulted his wife, called him a lair for several months — that'll do things to you."